to rat the obama administration. and south carolina presidential election. shooting down rockets and missiles is idea behind israel so-called iron dome. said to be effective in conflict with hamas. what. we look at the questions from the pentagon. >> 1,500 rockets were fired at israel from the gaza strip in eight day of fighting. the iron dome missile system said to intercepted most of them. modern warfare game changer in the middle east. >> iron dome, performed, fair to say remarkably well. in the recent escalation. >> only 55 out of the 1,500 ended up falling. >> the u.s. taxpayers invested $275 million to help israel build and seal the iron dome which can stop incoming rockets within a 2.5-mile to 44-mile range. israel outgoing defense minister gave panetta a model as a token of gratitude. >> small iron dome. >> but the u.s. army want mrs. than a model. it wants its own antimissile system. and congress would like a favorable discount given what the u.s. has already invested in the system. >> but instead of buying from israelis who already have technology,